Synergistic sensitization between Rh-MOF and Ru(bpy)32+ driving superior electrochemiluminescence performance for selective L-proline detection.

A highly sensitive and cost-effective electrochemiluminescent (ECL) method has been developed for the selective detection of L-proline, addressing the growing demand for rapid small-molecule screening in health diagnostics. The method integrates a porous material, a rhodium-based metal-organic framework (Rh-MOF), synthesized via a rapid one-pot procedure involving coordination between Rh(III) ions and 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine (TCPrz), onto an isostatic graphite electrode (ISGE). Functioning as an efficient porous sensitizing host, Rh-MOF significantly amplified the anodic ECL signal of Ru(bpy)32+, resulting in a 93-fold enhancement. The method demonstrated excellent analytical performance, with a wide linear range (100 pM-1 mM), low detection limit (67 pM), and high selectivity toward L-proline. Analysis of real serum samples assured high recovery and good precision, highlighting the practical applicability of the proposed method in clinical diagnostics. This study offers novel perspectives on the development of MOFs as efficient enhancer, combined with the outstanding performance of low-cost ISGE, demonstrating promising applications in the detection of small biomolecules.